Vinyl chloride resin composition for powder molding, vinyl chloride resin molded product, and laminate

ABSTRACT

Provided is a vinyl chloride resin composition for powder molding that can provide a molded product having superior flexibility at low temperatures. The vinyl chloride resin composition for powder molding includes (a) vinyl chloride resin particles, (b) a plasticizer, and (c) vinyl chloride resin fine particles having an average degree of polymerization of at least 1,000 and no greater than 5,000.

TECHNICAL FIELD

The present disclosure relates to a vinyl chloride resin composition forpowder molding that can provide a molded product having superiorflexibility at low temperatures, a vinyl chloride resin molded productformed through powder molding of the vinyl chloride resin compositionfor powder molding, and a laminate including the vinyl chloride resinmolded product and a foamed polyurethane molded product.

BACKGROUND

An automobile instrument panel has a structure in which a foamedpolyurethane layer is disposed between a substrate and a surface skinformed from a vinyl chloride resin. Over time, the surface skin formedfrom the vinyl chloride resin discolors and experiences a reduction inheat aging resistance. One main cause of discoloration and so forth ofthe surface skin is a chemical reaction that occurs as a result of atertiary amine used as a catalyst in formation of the foamedpolyurethane layer migrating to the surface skin formed from the vinylchloride resin. In order to prevent surface skin discoloring, a urethaneintegrated foamed molded product has been considered in which a granularcatcher agent that captures volatile organic compounds produced in afoamed polyurethane layer and that is coated with an open cell foamsheet is provided near locations at which the edges of the foamedpolyurethane layer are sealed by a surface skin and a substrate (forexample, refer to PTL 1). However, there are sections where the surfaceskin and the foamed polyurethane layer are in contact in this urethaneintegrated foamed molded product and, as a result, surface skindiscoloration due to the aforementioned chemical reaction cannot beprevented over a long period and heat aging resistance of the surfaceskin decreases.

On the other hand, a laminate has been considered in which a syntheticresin foamed layer is provided that joins a core material and a surfaceskin and in which the core material includes gas release holes forreleasing gas produced in the foamed layer (for example, refer to PTL2). However, the synthetic resin foamed layer and the surface skin arein contact in this laminate and, as a result, surface skin discolorationdue to the aforementioned chemical reaction cannot be prevented over along period and heat aging resistance of the surface skin decreases.

Furthermore, a molded product has been considered that includes apolyurethane molded product, a surface skin containing a vinyl chlorideresin that covers at least one surface of the urethane molded product,and an amine catcher layer disposed between the polyurethane moldedproduct and the surface skin (for example, refer to PTL 3). However, itis not possible to prevent migration of a tertiary amine to the surfaceskin formed from the vinyl chloride resin over a long period due tovolatility of the amine catcher. Therefore, surface skin discolorationdue to the aforementioned chemical reaction cannot be prevented over along period and heat aging resistance of the surface skin decreases inthis molded product.

On the other hand, a vinyl chloride resin composition for powder moldingthat includes a prescribed trimellitate plasticizer has been consideredas a raw material for a surface skin of an automobile interior material(for example, refer to PTL 4). However, it is necessary to increase theblended amount of the plasticizer in order to improve heat agingresistance of a surface skin material that is obtained through powdermolding of the vinyl chloride resin composition, which results in thesurface skin material feeling sticky due to the plasticizer. A vinylchloride resin composition for powder molding has also been consideredthat includes 100 parts by mass of vinyl chloride resin particles madefrom a vinyl chloride resin having an average degree of polymerizationof at least 1,500 and 110 parts by mass to 150 parts by mass of aprescribed trimellitate plasticizer (for example, refer to PTL 5).

CITATION LIST Patent Literature

PTL 1: JP 2007-216506 A

PTL 2: JP H8-90697 A

PTL 3: JP H4-26303 B

PTL 4: JP H2-138355 A

PTL 5: WO 2009/107463

SUMMARY Technical Problem

In order that fragments of a surface skin of an automobile instrumentpanel that is laminated with a foamed polyurethane layer are notscattered when the surface skin breaks as designed at low temperaturesupon expansion of an air bag, there has been demand in recent years foran automobile instrument panel including a surface skin having superiorflexibility at low temperatures. However, is has not been possible toachieve an automobile instrument panel including a surface skin such asdescribed above.

The present disclosure aims to solve a problem of provision of a vinylchloride resin composition for powder molding that can provide a moldedproduct having superior flexibility at low temperatures. Another problemthat the present disclosure aims to solve is provision of a vinylchloride resin molded product that is formed through powder molding ofthe vinyl chloride resin composition for powder molding described aboveand that has superior flexibility at low temperatures, and provision ofa laminate including the vinyl chloride resin molded product and afoamed polyurethane molded product.

Solution to Problem

As a result of diligent investigation in order to solve the problemsdescribed above, the present inventor discovered that a vinyl chlorideresin composition for powder molding including (a) vinyl chloride resinparticles, (b) a plasticizer, and (c) vinyl chloride resin fineparticles having a specific average degree of polymerization can providea molded product having particularly superior flexibility at lowtemperatures. This discovery led to the present disclosure.

A presently disclosed vinyl chloride resin composition for powdermolding includes (a) vinyl chloride resin particles, (b) a plasticizer,and (c) vinyl chloride resin fine particles having an average degree ofpolymerization of at least 1,000 and no greater than 5,000.

In the presently disclosed vinyl chloride resin composition for powdermolding, (b) the plasticizer is preferably at least one plasticizerselected from the group consisting of trimellitate plasticizers andpyromellitate plasticizers.

In the presently disclosed vinyl chloride resin composition for powdermolding, a vinyl chloride resin forming (a) the vinyl chloride resinparticles preferably has an average degree of polymerization of at least1,000 and no greater than 5,000.

In the presently disclosed vinyl chloride resin composition for powdermolding, (a) the vinyl chloride resin particles preferably have anaverage particle diameter of at least 50 μm and no greater than 500 μm,and (c) the vinyl chloride resin fine particles having the averagedegree of polymerization of at least 1,000 and no greater than 5,000preferably have an average particle diameter of at least 0.1 μm and nogreater than 10 μm.

In the presently disclosed vinyl chloride resin composition for powdermolding, an amount of (c) the vinyl chloride resin fine particles havingthe average degree of polymerization of at least 1,000 and no greaterthan 5,000 relative to a total amount of (a) the vinyl chloride resinparticles and (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000 is preferably at least 5 mass % and no greater than 35 mass %.

In the presently disclosed vinyl chloride resin composition for powdermolding, an amount of (b) the plasticizer per 100 parts by mass in totalof (a) the vinyl chloride resin particles and (c) the vinyl chlorideresin fine particles having the average degree of polymerization of atleast 1,000 and no greater than 5,000 is preferably at least 70 parts bymass and no greater than 200 parts by mass.

The presently disclosed vinyl chloride resin composition for powdermolding preferably further includes (d) vinyl chloride resin fineparticles having an average degree of polymerization of less than 1,000.

In the presently disclosed vinyl chloride resin composition for powdermolding, (a) the vinyl chloride resin particles preferably have anaverage particle diameter of at least 50 μm and no greater than 500 μm,(c) the vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000 preferablyhave an average particle diameter of at least 0.1 μm and no greater than10 μm, and (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 preferably have anaverage particle diameter of at least 0.1 μm and no greater than 10 μm.

In the presently disclosed vinyl chloride resin composition for powdermolding, an amount of (c) the vinyl chloride resin fine particles havingthe average degree of polymerization of at least 1,000 and no greaterthan 5,000 relative to a total amount of (a) the vinyl chloride resinparticles, (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000, and (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 is preferably atleast 3 mass % and no greater than 20 mass %, and an amount of (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000 relative to the total amount of (a)the vinyl chloride resin particles, (c) the vinyl chloride resin fineparticles having the average degree of polymerization of at least 1,000and no greater than 5,000, and (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than 1,000is preferably at least 2 mass % and no greater than 15 mass %.

In the presently disclosed vinyl chloride resin composition for powdermolding, an amount of (b) the plasticizer per 100 parts by mass in totalof (a) the vinyl chloride resin particles, (c) the vinyl chloride resinfine particles having the average degree of polymerization of at least1,000 and no greater than 5,000, and (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than 1,000is preferably at least 70 parts by mass and no greater than 200 parts bymass.

The presently disclosed vinyl chloride resin composition for powdermolding is preferably used for powder slush molding.

A presently disclosed vinyl chloride resin molded product is obtainablethrough powder molding of the vinyl chloride resin composition forpowder molding described above.

The vinyl chloride resin molded product is preferably used as a surfaceskin of an automobile instrument panel.

A presently disclosed laminate includes a foamed polyurethane moldedproduct and the vinyl chloride resin molded product described above. Thelaminate is preferably used as a laminate of an automobile instrumentpanel.

Advantageous Effect

The presently disclosed vinyl chloride resin composition for powdermolding can provide a molded product having superior flexibility at lowtemperatures.

DETAILED DESCRIPTION

(Vinyl Chloride Resin Composition for Powder Molding)

A presently disclosed vinyl chloride resin composition for powdermolding includes (a) vinyl chloride resin particles, (b) a plasticizer,and (c) vinyl chloride resin fine particles having an average degree ofpolymerization of at least 1,000 and no greater than 5,000, and mayoptionally include (d) vinyl chloride resin fine particles having anaverage degree of polymerization of less than 1,000 and additives.

<Vinyl Chloride Resin>

A vinyl chloride resin forming (a) the vinyl chloride resin particles,(c) the vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000, and (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000 may for example be a homopolymer ofvinyl chloride or a copolymer preferably including at least 50 mass % ofvinyl chloride units and more preferably at least 70 mass % of vinylchloride units. Specific examples of comonomers of vinyl chloridecopolymers include: olefins such as ethylene and propylene; halogenatedolefins such as allyl chloride, vinylidene chloride, vinyl fluoride, andtrifluorochloroethylene; carboxylic acid vinyl esters such as vinylacetate and vinyl propionate; vinyl ethers such as isobutyl vinyl etherand cetyl vinyl ether; allyl ethers such as allyl-3-chloro-2-oxy propylether and allyl glycidyl ether; unsaturated carboxylic acids, esters ofunsaturated carboxylic acids, and acid anhydrides of unsaturatedcarboxylic acids such as acrylic acid, maleic acid, itaconic acid,acrylic acid-2-hydroxyethyl, methyl methacrylate, monomethyl maleate,diethyl maleate, and maleic anhydride; unsaturated nitriles such asacrylonitrile and methacrylonitrile; acrylamides such as acrylamide,N-methylolacrylamide, acrylamido-2-methylpropane sulfonic acid, and(meth)acrylamidopropyltrimethylammonium chloride; and allyl amines andderivatives thereof such as allylamine benzoate anddiallyldimethylammonium chloride. The above examples of monomers aremerely some of the monomers (comonomers) that are copolymerizable withvinyl chloride. Further examples of various types of monomers that canbe used as comonomers are provided in pages 75-104 of “Polyvinylchloride” edited by the Vinyl Section of the Kinki Chemical SocietyJapan and published by Nikkan Kogyo Shimbun, Ltd. (1988). Any one ofthese monomers or any two or more of these monomers may be used.Moreover, the vinyl chloride resin forming (a) the vinyl chloride resinparticles, (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000, and (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 may include a resinformed by graft polymerization of (1) vinyl chloride or (2) vinylchloride and a copolymerizable comonomer such as described above with aresin such as an ethylene-vinyl acetate copolymer, an ethylene-methylmethacrylate copolymer, an ethylene-ethyl acrylate copolymer, or achlorinated polyethylene.

The present description uses the term “(meth)acryl” to refer to eitheror both of acryl and methacryl.

Conventionally known production methods such as suspensionpolymerization, emulsion polymerization, solution polymerization, andbulk polymerization can be used to produce the vinyl chloride resin.

In the vinyl chloride resin composition for powder molding, (a) thevinyl chloride resin particles function as a matrix resin. Moreover, (c)the vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000 and (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000 function as a dusting agent (powderfluidity modifier) described further below. It is preferable that (a)the vinyl chloride resin particles are produced by suspensionpolymerization. Moreover, it is preferable that (c) the vinyl chlorideresin fine particles having the average degree of polymerization of atleast 1,000 and no greater than 5,000 and (d) the vinyl chloride resinfine particles having the average degree of polymerization of less than1,000 are produced by emulsion polymerization.

<Vinyl Chloride Resin Particles>

An average degree of polymerization of a vinyl chloride resin forming(a) the vinyl chloride resin particles is preferably at least 1,000 andno greater than 5,000, more preferably at least 1,500 and no greaterthan 5,000, further preferably greater than 2,000 and no greater than5,000, even further preferably greater than 2,000 and no greater than4,000, particularly preferably greater than 2,000 and no greater than3,500, and most preferably greater than 2,000 and no greater than 3,000.As a result of the average degree of polymerization of the vinylchloride resin forming (a) the vinyl chloride resin particles being inthe range described above, favorable fluidity and meltability can beobtained during powder molding of the vinyl chloride resin compositionfor powder molding and a vinyl chloride resin molded product formedthrough powder molding of the vinyl chloride resin composition forpowder molding can be provided with favorable heat aging resistance.Note that the average degree of polymerization is measured in accordancewith JIS K6720-2.

No specific limitations are placed on the average particle diameter of(a) the vinyl chloride resin particles. The average particle diameter ispreferably at least 50 μm and no greater than 500 μm, more preferably atleast 50 μm and no greater than 250 μm, and particularly preferably atleast 100 μm and no greater than 200 μm. As a result of the averageparticle diameter of (a) the vinyl chloride resin particles being in therange described above, powder fluidity of the vinyl chloride resincomposition for powder molding and smoothness of a vinyl chloride resinmolded product formed through powder molding of the vinyl chloride resincomposition for powder molding are improved. The average particlediameter of (a) the vinyl chloride resin particles is measured by alaser diffraction method in accordance with JIS Z8825 using, forexample, a SALD-2300 produced by Shimadzu Corporation.

Note that (a) the vinyl chloride resin particles normally have aparticle diameter of at least 30 μm.

<Vinyl Chloride Resin Fine Particles Having Average Degree ofPolymerization of at Least 1,000 and No Greater than 5,000>

(c) The vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000 function as adusting agent for improving powder fluidity of the vinyl chloride resincomposition for powder molding, and are distinct from (a) the vinylchloride resin particles. It is actually possible to visually confirmthe difference in fluidity of (a) the vinyl chloride resin particles and(c) the vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000.

The average particle diameter of (c) the vinyl chloride resin fineparticles having the average degree of polymerization of at least 1,000and no greater than 5,000 is preferably at least 0.1 μm and no greaterthan 10 μm.

Furthermore, (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000 normally have a particle diameter of less than 30 μm.

The average particle diameter of (c) the vinyl chloride resin fineparticles having the average degree of polymerization of at least 1,000and no greater than 5,000 is measured by a laser diffraction method inaccordance with JIS Z8825 using, for example, a SALD-2300 produced byShimadzu Corporation.

The average degree of polymerization of a vinyl chloride resin forming(c) the vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000 is preferablyat least 1,200 and no greater than 5,000, more preferably greater than1,500 and no greater than 5,000, further preferably greater than 1,500and no greater than 4,000, even further preferably greater than 1,500and no greater than 3,000, particularly preferably greater than 2,000and no greater than 3,000, and most preferably greater than 2,000 and nogreater than 2,500. As a result of the average degree of polymerizationof the vinyl chloride resin forming (c) the vinyl chloride resin fineparticles having the average degree of polymerization of at least 1,000and no greater than 5,000 being in the range described above,flexibility at low temperatures and heat aging resistance (tensileproperties after heating) of a vinyl chloride resin molded productobtained through powder molding of the vinyl chloride resin compositionfor powder molding are improved.

<Vinyl Chloride Resin Fine Particles Having Average Degree ofPolymerization of Less than 1,000>

The presently disclosed vinyl chloride resin composition for powdermolding preferably further includes (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than1,000. (d) The vinyl chloride resin fine particles having the averagedegree of polymerization of less than 1,000 function as a dusting agentfor improving powder fluidity of the vinyl chloride resin compositionfor powder molding and are distinct from (a) the vinyl chloride resinparticles and (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000.

The average particle diameter of (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than 1,000is preferably at least 0.1 μm and no greater than 10 μm.

Furthermore, (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 normally have aparticle diameter of less than 30 μm.

The average particle diameter of (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than 1,000is measured by a laser diffraction method in accordance with JIS Z8825using, for example, a SALD-2300 produced by Shimadzu Corporation.

The average degree of polymerization of a vinyl chloride resin forming(d) the vinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000 is preferably at least 300 and lessthan 1,000, more preferably at least 500 and no greater than 950, andparticularly preferably at least 600 and no greater than 900. As aresult of the average degree of polymerization of the vinyl chlorideresin forming (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 being in the rangedescribed above, powder fluidity of the vinyl chloride resin compositionfor powder molding and meltability of the composition in a moldingprocess can be improved.

<Content Ratio of Vinyl Chloride Resin Particles and Vinyl ChlorideResin Fine Particles>

Herein, in a situation in which the presently disclosed vinyl chlorideresin composition for powder molding does not include (d) the vinylchloride resin fine particles having the average degree ofpolymerization of less than 1,000, the amount of (a) the vinyl chlorideresin particles relative to the total amount (100 mass %) of (a) thevinyl chloride resin particles and (c) the vinyl chloride resin fineparticles having the average degree of polymerization of at least 1,000and no greater than 5,000 is preferably at least 65 mass % and nogreater than 95 mass %, more preferably at least 70 mass % and nogreater than 92 mass %, and particularly preferably at least 72 mass %and no greater than 88 mass %. As a result of the amount of (a) thevinyl chloride resin particles being in the range described above,powder fluidity of the vinyl chloride resin composition for powdermolding can be improved, and flexibility at low temperatures and heataging resistance (tensile properties after heating) of a vinyl chlorideresin molded product obtained through powder molding of the vinylchloride resin composition for powder molding can be improved.

Furthermore, in the situation in which the presently disclosed vinylchloride resin composition for powder molding does not include (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000, the amount of (c) the vinyl chlorideresin fine particles having the average degree of polymerization of atleast 1,000 and no greater than 5,000 relative to the total amount (100mass %) of (a) the vinyl chloride resin particles and (c) the vinylchloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000 is preferablyat least 5 mass % and no greater than 35 mass %, more preferably atleast 8 mass % and no greater than 30 mass %, and particularlypreferably at least 12 mass % and no greater than 28 mass %. As a resultof the amount of (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000 being in the range described above, powder fluidity of the vinylchloride resin composition for powder molding can be improved, andflexibility at low temperatures and heat aging resistance (tensileproperties after heating) of a vinyl chloride resin molded productobtained through powder molding of the vinyl chloride resin compositionfor powder molding can be improved.

On the other hand, in a situation in which the presently disclosed vinylchloride resin composition for powder molding includes (d) the vinylchloride resin fine particles having the average degree ofpolymerization of less than 1,000, the amount of (d) the vinyl chlorideresin fine particles having the average degree of polymerization of lessthan 1,000 relative to the total amount (100 mass %) of (a) the vinylchloride resin particles, (c) the vinyl chloride resin fine particleshaving the average degree of polymerization of at least 1,000 and nogreater than 5,000, and (d) the vinyl chloride resin fine particleshaving the average degree of polymerization of less than 1,000 ispreferably at least 2 mass % and no greater than 15 mass %, morepreferably at least 3 mass % and no greater than 12 mass %, andparticularly preferably at least 4 mass % and no greater than 11 mass %.As a result of the amount of (d) the vinyl chloride resin fine particleshaving the average degree of polymerization of less than 1,000 being inthe range described above, powder fluidity of the vinyl chloride resincomposition for powder molding and meltability of the composition in amolding process can be improved. Moreover, a vinyl chloride resin moldedproduct obtained through powder molding of the vinyl chloride resincomposition for powder molding has a superior balance of flexibility atlow temperatures and heat aging resistance (tensile properties afterheating).

In the situation in which the presently disclosed vinyl chloride resincomposition for powder molding includes (d) the vinyl chloride resinfine particles having the average degree of polymerization of less than1,000, the amount of (a) the vinyl chloride resin particles relative tothe total amount (100 mass %) of (a) the vinyl chloride resin particles,(c) the vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000, and (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000 is preferably at least 65 mass % andno greater than 95 mass %, more preferably at least 70 mass % and nogreater than 92 mass %, and particularly preferably at least 72 mass %and no greater than 88 mass %. As a result of the amount of (a) thevinyl chloride resin particles being in the range described above,powder fluidity of the vinyl chloride resin composition for powdermolding can be improved, and flexibility at low temperatures and heataging resistance (tensile properties after heating) of a vinyl chlorideresin molded product obtained through powder molding of the vinylchloride resin composition for powder molding can be improved.

Furthermore, in the situation in which the presently disclosed vinylchloride resin composition for powder molding includes (d) the vinylchloride resin fine particles having the average degree ofpolymerization of less than 1,000, the amount of (c) the vinyl chlorideresin fine particles having the average degree of polymerization of atleast 1,000 and no greater than 5,000 relative to the total amount (100mass %) of (a) the vinyl chloride resin particles, (c) the vinylchloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000, and (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000 is preferably at least 3 mass % and nogreater than 20 mass %, more preferably at least 5 mass % and no greaterthan 18 mass %, and particularly preferably at least 8 mass % and nogreater than 17 mass %. As a result of the amount of (c) the vinylchloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000 being in therange described above, powder fluidity of the vinyl chloride resincomposition for powder molding and meltability of the composition in amolding process can be improved.

<Plasticizer>

No specific limitations are placed on (b) the plasticizer included inthe presently disclosed vinyl chloride resin composition for powdermolding which may for example be a trimellitate plasticizer, apyromellitate plasticizer, or another plasticizer. Among suchplasticizers, (b) the plasticizer is preferably at least one plasticizerselected from the group consisting of trimellitate plasticizers andpyromellitate plasticizers. A preferable example of a trimellitateplasticizer is an ester compound of trimellitic acid and a monohydricalcohol, and a preferable example of a pyromellitate plasticizer is anester compound of pyromellitic acid and a monohydric alcohol.

[Trimellitate Plasticizer]

Specific examples of trimellitate plasticizers that may be used includetri-n-hexyl trimellitate, tri-n-heptyl trimellitate, tri-n-octyltrimellitate, tri(2-ethylhexyl) trimellitate, tri-n-nonyl trimellitate,tri-n-decyl trimellitate, triisodecyl trimellitate, tri-n-undecyltrimellitate, tri-n-dodecyl trimellitate, and tri-n-alkyl trimellitates(esters including two or more types of alkyl groups having differingcarbon numbers of 6-12 in molecules thereof).

One specific preferable example of a trimellitate plasticizer is acompound represented by formula (1) shown below.

In formula (1), R¹, R², and R³ are alkyl groups that may be the same ordifferent.

A straight chain ratio of each of R¹, R², and R³ is preferably at least90 mol % and more preferably at least 95 mol %. The proportion of alkylgroups having a carbon number of no greater than 7 relative to all alkylgroups R¹, R², and R³ is preferably at least 0 mol % and no greater than10 mol %. The proportion of alkyl groups having a carbon number of 8 or9 relative to all alkyl groups R¹, R², and R³ is preferably at least 5mol % and no greater than 100 mol %, more preferably at least 40 mol %and no greater than 95 mol %, and particularly preferably at least 75mol % and no greater than 95 mol %. The proportion of alkyl groupshaving a carbon number of 10 relative to all alkyl groups R², and R³ ispreferably at least 0 mol % and no greater than 95 mol %, morepreferably at least 5 mol % and no greater than 60 mol %, andparticularly preferably at least 5 mol % and no greater than 25 mol %.The proportion of alkyl groups having a carbon number of at least 11relative to all alkyl groups R¹, R², and R³ is preferably at least 0 mol% and no greater than 10 mol %. Note that the straight chain ratios ofR¹, R², and R³ are the proportions of straight chain alkyl groupsrelative to all alkyl groups for R¹, R², and R³ respectively.

Specific examples of straight chain alkyl groups that can form R¹, R²,and R³ in formula (1) include a methyl group, an ethyl group, ann-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group,an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group,an n-undecyl group, an n-dodecyl group, an n-tridecyl group, ann-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, and ann-stearyl group. Specific examples of branched alkyl group that can formR¹, R², and R³ in formula (1) include an i-propyl group, an i-butylgroup, an i-pentyl group, an i-hexyl group, an i-heptyl group, ani-octyl group, an i-nonyl group, an i-decyl group, an i-undecyl group,an i-dodecyl group, an i-tridecyl group, an i-pentadecyl group, ani-hexadecyl group, an i-heptadecyl group, an i-octadecyl group, at-butyl group, a t-pentyl group, a t-hexyl group, a t-heptyl group, at-octyl group, a t-nonyl group, a t-decyl group, a t-undecyl group, at-dodecyl group, a t-tridecyl group, a t-pentadecyl group, a t-hexadecylgroup, a t-heptadecyl group, a t-octadecyl group, and a 2-ethylhexylgroup.

The trimellitate plasticizer may be a single compound or may be amixture.

[Pyromellitate Plasticizer]

Specific examples of pyromellitate plasticizers that may be used includetetraalkyl pyromellitates such as tetra-n-hexyl pyromellitate,tetra-n-octyl pyromellitate, tetra(2-ethylhexyl) pyromellitate,tetra-n-decyl pyromellitate, tetra-i-decyl pyromellitate, andtetra-n-alkyl pyromellitates (esters including two or more types ofalkyl groups having differing carbon numbers of 6-12, and preferably7-10, in molecules thereof). Among the above examples, tetraalkylpyromellitates in which the ester groups each have a carbon number of6-10 are preferable, tetraalkyl pyromellitates in which the ester groupseach have a carbon number of 8-10, such as tetra-n-octyl pyromellitate,tetra(2-ethylhexyl) pyromellitate, and tetra-n-decyl pyromellitate, aremore preferable, and tetraalkyl pyromellitates in which the ester groupseach have a carbon number of 8, such as tetra-n-octyl pyromellitate andtetra(2-ethylhexyl) pyromellitate, are particularly preferable.

The pyromellitate plasticizer may be a single compound or may be amixture.

[Other Plasticizers]

Examples of other plasticizers besides the trimellitate plasticizer andthe pyromellitate plasticizer that may be used include primaryplasticizers and secondary plasticizers listed below.

Examples of so-called primary plasticizers include:

epoxidized vegetable oils such as epoxidized soybean oil and epoxidizedlinseed oil;

phthalic acid derivatives such as dimethyl phthalate, diethyl phthalate,di-n-butyl phthalate, diisobutyl phthalate, di-n-heptyl phthalate,di(2-ethylhexyl) phthalate, di-n-octyl phthalate, di-n-nonyl phthalate,di-n-decyl phthalate, diisodecyl phthalate, di-n-undecyl phthalate,di-n-dodecyl phthalate, di-n-tridecyl phthalate, dicyclohexyl phthalate,diphenyl phthalate, dibenzyl phthalate, and n-butylbenzyl phthalate;

isophthalic acid derivatives such as dimethyl isophthalate,di(2-ethylhexyl) isophthalate, and diisooctyl isophthalate;

tetrahydrophthalic acid derivatives such as di(2-ethylhexyl)tetrahydrophthalate, di-n-octyl tetrahydrophthalate, and diisodecyltetrahydrophthalate;

adipic acid derivatives such as di-n-butyl adipate, di(2-ethylhexyl)adipate, diisononyl adipate, and diisodecyl adipate;

azelaic acid derivatives such as di(2-ethylhexyl) azelate, diisooctylazelate, and di-n-hexyl azelate;

sebacic acid derivatives such as di-n-butyl sebacate, di(2-ethylhexyl)sebacate, diisodecyl sebacate, and di(2-butyloctyl) sebacate;

maleic acid derivatives such as dimethyl maleate, diethyl maleate,di-n-butyl maleate, and di(2-ethylhexyl) maleate;

fumaric acid derivatives such as di-n-butyl fumarate anddi(2-ethylhexyl) fumarate;

citric acid derivatives such as triethyl citrate, tri-n-butyl citrate,acetyltriethyl citrate, and acetyltri(2-ethylhexyl) citrate;

itaconic acid derivatives such as monomethyl itaconate, mono-n-butylitaconate, dimethyl itaconate, diethyl itaconate, di-n-butyl itaconate,and di(2-ethylhexyl) itaconate;

oleic acid derivatives such as butyl oleate, glyceryl monooleate, anddiethylene glycol monooleate;

ricinoleic acid derivatives such as methylacetyl ricinoleate,n-butylacetyl ricinoleate, glyceryl monoricinoleate, and diethyleneglycol monoricinoleate;

stearic acid derivatives such as n-butyl stearate and diethylene glycoldi stearate;

other fatty acid derivatives such as diethylene glycol monolaurate,diethylene glycol dipelargonate, and pentaerythritol fatty acid esters;

phosphoric acid derivatives such as triethyl phosphate, tri-n-butylphosphate, tri(2-ethylhexyl) phosphate, tri-n-butoxyethyl phosphate,triphenyl phosphate, cresyl diphenyl phosphate, tricresyl phosphate,trixylenyl phosphate, and tris(chloroethyl) phosphate;

glycol derivatives such as diethylene glycol dibenzoate, dipropyleneglycol dibenzoate, triethylene glycol dibenzoate, triethylene glycoldi(2-ethylbutyrate), triethylene glycol di(2-ethylhexoate), and dibutylmethylenebis(thioglycolate);

glycerin derivatives such as glycerol monoacetate, glycerol triacetate,and glycerol tributyrate;

epoxy derivatives such as epoxy hexahydro diisodecyl phthalate, epoxytriglyceride, epoxidized octyl oleate, and epoxidized decyl oleate; and

polyester plasticizers such as adipic acid polyesters, sebacic acidpolyesters, and phthalic acid polyesters.

Examples of so-called secondary plasticizers include chlorinatedparaffin, fatty acid esters of glycol such as triethylene glycoldicaprylate, n-butyl epoxy stearate, phenyl oleate, and methyldihydroabietate.

Any one or any two or more of these other plasticizers may be used inthe presently disclosed vinyl chloride resin composition for powdermolding. In a situation in which a secondary plasticizer is used, aprimary plasticizer of equivalent or greater mass is preferably used incombination with the secondary plasticizer.

Among the other plasticizers listed above, epoxidized plant oils arepreferable, and epoxidized soybean oil is more preferable.

The amount of (b) the plasticizer per 100 parts by mass in total of (a)the vinyl chloride resin particles, (c) the vinyl chloride resin fineparticles having the average degree of polymerization of at least 1,000and no greater than 5,000, and (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than1,000, which are added as required, is preferably at least 70 parts bymass and no greater than 200 parts by mass, more preferably at least 80parts by mass and no greater than 180 parts by mass, further preferablyat least 90 parts by mass and no greater than 160 parts by mass,particularly preferably at least 100 parts by mass and no greater than150 parts by mass, and most preferably at least 115 parts by mass and nogreater than 125 parts by mass. As a result of the amount of (b) theplasticizer being in the range described above, a vinyl chloride resinmolded product obtained through powder molding of the vinyl chlorideresin composition for powder molding has better heat aging resistance,and powder molding properties of the vinyl chloride resin compositionfor powder molding are improved due to good absorption of (b) theplasticizer by (a) the vinyl chloride resin particles.

In a situation in which (b) the plasticizer includes both a trimellitateplasticizer and a pyromellitate plasticizer, no specific limitations areplaced on the content ratio of the trimellitate plasticizer and thepyromellitate plasticizer. The content ratio of the trimellitateplasticizer and the pyromellitate plasticizer in (b) the plasticizer(trimellitate plasticizer/pyromellitate plasticizer), as a mass ratio,is preferably from 10/1 to 1/10, more preferably from 8/1 to 1/8,further preferably from 4/1 to 1/4, and particularly preferably from 4/1to 1/1.

In a situation in which (b) the plasticizer includes any of the otherplasticizers described above, the amount of the other plasticizers in(b) the plasticizer is preferably no greater than 10 mass %, morepreferably at least 1 mass % and no greater than 10 mass %, andparticularly preferably at least 2 mass % and no greater than 5 mass %.

<Additives>

Besides (a) the vinyl chloride resin particles, (b) the plasticizer, (c)the vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000, and (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000, the presently disclosed vinylchloride resin composition for powder molding may further includevarious additives. Although no specific limitations are placed on theseadditives, examples of additives that may be used include perchloricacid-treated hydrotalcite, zeolite, fatty acid metal salts, dustingagents (powder fluidity modifiers) other than (c) the vinyl chlorideresin fine particles having the average degree of polymerization of atleast 1,000 and no greater than 5,000 and (d) the vinyl chloride resinfine particles having the average degree of polymerization of less than1,000 (hereinafter also referred to as “other dusting agents”), andother additives.

[Perchloric Acid-Treated Hydrotalcite]

The perchloric acid-treated hydrotalcite that may be included in thepresently disclosed vinyl chloride resin composition for powder moldingcan be easily produced by, for example, addition and stirring ofhydrotalcite with a dilute aqueous solution of perchloric acid, followedby filtration, dehydration, and drying as required. Through thisprocess, at least some of the carbonate anions (CO₃ ²⁻) in thehydrotalcite are substituted with perchlorate anions (ClO₄ ⁻) (note that2 mol of perchlorate anions are substituted per 1 mol of carbonateanions). The molar ratio of hydrotalcite and perchloric acid may befreely set, although a ratio of from 0.1 mol to 2 mol of perchloric acidrelative to 1 mol of hydrotalcite is typical.

The substitution ratio of carbonate anions in the untreated(unsubstituted) hydrotalcite by perchlorate anions is preferably atleast 50 mol %, more preferably at least 70 mol %, and particularlypreferably at least 85 mol %. Moreover, the substitution ratio ofcarbonate anions in the untreated (unsubstituted) hydrotalcite byperchlorate anions is preferably no greater than 95 mol %. As a resultof the substitution ratio of carbonate anions in the untreated(unsubstituted) hydrotalcite by perchlorate anions being in the rangedescribed above, a vinyl chloride resin molded product formed throughpowder molding of the vinyl chloride resin composition for powdermolding can be provided with favorable flexibility at low temperatures.

Hydrotalcite is a non-stoichiometric compound represented by a generalformula: [Mg_(1-x)Al_(x)(OH)₂]^(x+)[(CO₃)_(x/2).mH₂O]^(x−), and is aninorganic substance having a layered crystal structure formed by apositively charged basic layer of [Mg_(1-x)Al_(x)(OH)₂]^(x+) and anegatively charged intermediate layer of [(CO₃)_(x/2).mH₂O]^(x−). In thegeneral formula shown above, x represents a number that is greater than0 and no greater than 0.33. Natural hydrotalcite is represented byMg₆Al₂(OH)₁₆CO₃.4H₂O. On the other hand, a synthetic hydrotalciterepresented by Mg_(4.5)Al₂(OH)₁₃CO₃.3.5H₂O is commercially available.Synthetic hydrotalcite can for example be synthesized by a methoddescribed in JP S61-174270 B.

The amount of the perchloric acid-treated hydrotalcite per 100 parts bymass in total of (a) the vinyl chloride resin particles, (c) the vinylchloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000, and (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000, which are added as required, ispreferably at least 0.5 parts by mass and no greater than 7 parts bymass, more preferably at least 1 part by mass and no greater than 6parts by mass, and particularly preferably at least 1.5 parts by massand no greater than 5.5 parts by mass. As a result of the amount of theperchloric acid-treated hydrotalcite being in the range described above,a vinyl chloride resin molded product formed through powder molding ofthe vinyl chloride resin composition for powder molding can be providedwith favorable flexibility at low temperatures.

[Zeolite]

The presently disclosed vinyl chloride resin composition for powdermolding may include a zeolite as a stabilizer. A zeolite is a compoundrepresented by a general formula: M_(x/n).[(AlO₂)_(x).(SiO₂)_(y)].zH₂O(in the general formula, M is a metal ion of valency n, x+y is thenumber of tetrahedra per unit cell, and z is the number of moles ofwater). Examples of M in the general formula include monovalent anddivalent metals such as Na, Li, Ca, Mg, and Zn, and mixtures thereof.

No specific limitations are placed on the amount of the zeolite that isincluded. The amount of the zeolite per 100 parts by mass in total of(a) the vinyl chloride resin particles, (c) the vinyl chloride resinfine particles having the average degree of polymerization of at least1,000 and no greater than 5,000, and (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than1,000, which are added as required, is preferably at least 0.1 parts bymass and no greater than 5 parts by mass.

[Fatty Acid Metal Salt]

The fatty acid metal salt that may be included in the presentlydisclosed vinyl chloride resin composition for powder molding ispreferably a metal salt of a monobasic fatty acid, more preferably ametal salt of a monobasic fatty acid having a carbon number of at least12 and no greater than 24, and particularly preferably a metal salt of amonobasic fatty acid having a carbon number of at least 15 and nogreater than 21. Specific examples of the fatty acid metal salt includelithium stearate, magnesium stearate, aluminum stearate, calciumstearate, strontium stearate, barium stearate, zinc stearate, calciumlaurate, barium laurate, zinc laurate, barium 2-ethylhexanoate, zinc2-ethylhexanoate, barium ricinoleate, and zinc ricinoleate. The metal inthe fatty acid metal salt is preferably a metal that can producepolyvalent cations, more preferably a metal that can produce divalentcations, further preferably a metal from periods 3-6 of the periodictable that can produce divalent cations, and particularly preferably ametal from period 4 of the periodic table that can produce divalentcations. The fatty acid metal salt is most preferably zinc stearate.

The amount of the fatty acid metal salt per 100 parts by mass in totalof (a) the vinyl chloride resin particles, (c) the vinyl chloride resinfine particles having the average degree of polymerization of at least1,000 and no greater than 5,000, and (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than1,000, which are added as required, is preferably at least 0.05 parts bymass and no greater than 5 parts by mass, more preferably at least 0.1parts by mass and no greater than 1 part by mass, and particularlypreferably at least 0.1 parts by mass and no greater than 0.5 parts bymass. As a result of the amount of the fatty acid metal salt being inthe range described above, a vinyl chloride resin molded product formedthrough powder molding of the vinyl chloride resin composition forpowder molding can be provided with favorable flexibility at lowtemperatures and a color difference value thereof can be reduced.

[Other Dusting Agents]

Examples of other dusting agents (powder fluidity modifiers) besides (c)the vinyl chloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000 and (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000 that may be included in the presentlydisclosed vinyl chloride resin composition for powder molding include:inorganic fine particles such as calcium carbonate, talc, and aluminumoxide; and organic fine particles such as polyacrylonitrile resin fineparticles, poly(meth)acrylate resin fine particles, polystyrene resinfine particles, polyethylene resin fine particles, polypropylene resinfine particles, polyester resin fine particles, and polyamide resin fineparticles. Among these examples, inorganic fine particles having anaverage particle diameter of at least 10 nm and no greater than 100 nmare preferable.

The amount of other dusting agents that are included is not limited to aspecific range. The amount of other dusting agents per 100 parts by massin total of (a) the vinyl chloride resin particles, (c) the vinylchloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000, and (d) thevinyl chloride resin fine particles having the average degree ofpolymerization of less than 1,000, which are added as required, ispreferably no greater than 20 parts by mass, and more preferably nogreater than 10 parts by mass.

[Other Additives]

Examples of other additives that may be included in the presentlydisclosed vinyl chloride resin composition for powder molding includecolorants, impact modifiers, perchloric acid compounds other thanperchloric acid-treated hydrotalcite (for example, sodium perchlorateand potassium perchlorate), antioxidants, fungicides, flame retardants,antistatic agents, fillers, light stabilizers, foaming agents,β-diketones, and mold release agents.

Specific examples of colorants include quinacridone pigments, perylenepigments, condensed polyazo pigments, isoindolinone pigments, copperphthalocyanine pigments, titanium white, and carbon black. Any one ofthese pigments or any two or more of these pigments may be used.

A quinacridone pigment is obtained through concentrated sulfuric acidtreatment of a p-phenylene dianthranilic acid and has a hue fromyellowish red to reddish purple. Specific examples of quinacridonepigments include quinacridone red, quinacridone magenta, andquinacridone violet.

A perylene pigment is obtained through a condensation reaction ofperylene-3,4,9,10-tetracarboxylic anhydride and an aromatic primaryamine and has a hue from red to red-purple/brown. Specific examples ofperylene pigments include perylene red, perylene orange, perylenemaroon, perylene vermilion, and perylene bordeaux.

A condensed polyazo pigment is obtained through condensation of an azopigment in a solvent to achieve a high molecular weight and has a hue ofa yellow or red pigment. Specific examples of condensed polyazo pigmentsinclude polyazo red, polyazo yellow, chromophthal orange, chromophthalred, and chromophthal scarlet.

An isoindolinone pigment is obtained through a condensation reaction of4,5,6,7-tetrachloroisoindolinone and an aromatic primary diamine and hasa hue from greenish yellow to red/brown. A specific example of anisoindolinone pigment is isoindolinone yellow.

A copper phthalocyanine pigment is a pigment in which copper iscoordinated with a phthalocyanine and has a hue from yellowish green tobright blue. Specific examples of copper phthalocyanine pigments includephthalocyanine green and phthalocyanine blue.

Titanium white is a white pigment made from titanium dioxide. Titaniumwhite has high opacity and exists in anatase form and rutile form.

Carbon black is a black pigment having carbon as a main component andalso including oxygen, hydrogen, and nitrogen. Specific examples ofcarbon black include thermal black, acetylene black, channel black,furnace black, lamp black, and bone black.

Specific examples of impact modifiers include anacrylonitrile-butadiene-styrene copolymer, a methylmethacrylate-butadiene-styrene copolymer, a chlorinated polyethylene, anethylene-vinyl acetate copolymer, and a chlorosulfonated polyethylene.One impact modifier or two or more impact modifiers may be used in thepresently disclosed vinyl chloride resin composition for powder molding.Note that the impact modifier is dispersed as a heterogeneous phase offine elastic particles in the vinyl chloride resin composition forpowder molding. In the vinyl chloride resin composition for powdermolding, polar groups and chains graft polymerized with the elasticparticles are compatible with (a) the vinyl chloride resin particles andimprove impact resistance of the vinyl chloride resin composition forpowder molding.

Specific examples of antioxidants include phenolic antioxidants,sulfuric antioxidants, phosphoric antioxidants, and phosphiteantioxidants.

Specific examples of fungicides include aliphatic ester fungicides,hydrocarbon fungicides, organic nitrogen fungicides, and organicnitrogen sulfur fungicides.

Specific examples of flame retardants include halogen-containing flameretardants such as chlorinated paraffin, phosphoric flame retardantssuch as phosphate esters, and inorganic hydroxides such as magnesiumhydroxide and aluminum hydroxide.

Specific examples of antistatic agents include: anionic antistaticagents such as fatty acid salts, higher alcohol sulfuric acid esters,and sulfonic acid salts; cationic antistatic agents such as aliphaticamine salts and quaternary ammonium salts; and non-ionic antistaticagents such as polyoxyethylene alkyl ethers and polyoxyethylene alkylphenol ethers.

Specific examples of fillers include silica, talc, mica, calciumcarbonate, and clay.

Specific examples of light stabilizers include ultraviolet absorbersbased on benzotriazoles, benzophenone, and nickel chelate, and hinderedamine light stabilizers.

Specific examples of foaming agents include: organic foaming agents suchas azo compounds (for example, azodicarbonamides andazobisisobutyronitrile), nitroso compounds (for example,N,N′-dinitrosopentamethylenetetramine), and sulfonyl hydrazide compounds(for example p-toluenesulfonyl hydrazide and p,p-oxybis(benzenesulfonylhydrazide)); and gaseous foaming agents such as chlorofluorocarbons,carbon dioxide gas, water, and volatile hydrocarbons (for examplepentane), and microcapsules containing any of these gaseous foamingagents.

A β-diketone can be used to more effectively suppress variation ininitial color of a vinyl chloride resin molded product obtained throughpowder molding of the presently disclosed vinyl chloride resincomposition for powder molding. Specific examples of β-diketones includedibenzoylmethane, stearoylbenzoylmethane, and palmitoylbenzoylmethane.Any one of these β-diketones may be used alone or a combination of anytwo or more of these β-diketones may be used.

No specific limitations are placed on the amount of the β-diketone thatis included. The amount of the β-diketone per 100 parts by mass in totalof (a) the vinyl chloride resin particles, (c) the vinyl chloride resinfine particles having the average degree of polymerization of at least1,000 and no greater than 5,000, and (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than1,000, which are added as required, is preferably at least 0.1 parts bymass or no greater than 5 parts by mass.

Specific examples of mold release agents include hydroxygroup-containing saturated fatty acids such as hydroxystearic acid,hydroxymyristic acid, and hydroxylauric acid. Any one of these moldrelease agents may be used alone or a combination of any two or more ofthese mold release agents may be used. No specific limitations areplaced on the amount of the mold release agent that is included. Theamount of the mold release agent per 100 parts by mass in total of (a)the vinyl chloride resin particles, (c) the vinyl chloride resin fineparticles having the average degree of polymerization of at least 1,000and no greater than 5,000, and (d) the vinyl chloride resin fineparticles having the average degree of polymerization of less than1,000, which are added as required, is preferably at least 0.1 parts bymass and no greater than 3 parts by mass.

<Production Method of Vinyl Chloride Resin Composition for PowderMolding>

The presently disclosed vinyl chloride resin composition for powdermolding can be produced by mixing the components described above.

No specific limitations are placed on the method used to mix (a) thevinyl chloride resin particles, (b) the plasticizer, (c) the vinylchloride resin fine particles having the average degree ofpolymerization of at least 1,000 and no greater than 5,000, and also, asrequired, (d) the vinyl chloride resin fine particles having the averagedegree of polymerization of less than 1,000 and other additives. Oneexample of a preferable mixing method involves mixing all of thecomponents with the exception of the plasticizer and the dusting agent(including (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000 and (d) the vinyl chloride resin fine particles having the averagedegree of polymerization of less than 1,000) by dry blending andsubsequently mixing in the plasticizer and the dusting agent in order.The dry blending is preferably carried out using a Henschel mixer. Thetemperature during dry blending is preferably at least 50° C. and nogreater than 100° C., and more preferably at least 70° C. and no greaterthan 80° C.

(Vinyl Chloride Resin Molded Product)

A presently disclosed vinyl chloride resin molded product is obtainedthrough powder molding, and preferably through powder slush molding, ofthe presently disclosed vinyl chloride resin composition for powdermolding described above. The mold temperature during powder slushmolding is preferably at least 200° C. and no greater than 300° C., andmore preferably at least 220° C. and no greater than 280° C.

In production of the presently disclosed vinyl chloride resin moldedproduct, the presently disclosed vinyl chloride resin composition forpowder molding is for example sprinkled onto a mold having a temperaturein the aforementioned range. The vinyl chloride resin composition forpowder molding is initially left for at least 5 seconds and no greaterthan 30 seconds and, after shaking off any excess vinyl chloride resincomposition for powder molding, is then further left for at least 30seconds and no greater than 3 minutes. The mold is subsequently cooledto at least 10° C. and no greater than 60° C. and the presentlydisclosed vinyl chloride resin molded product obtained thereby isremoved from the mold.

The presently disclosed vinyl chloride resin molded product is highlysuitable for use as a surface skin of an automobile interior materialsuch as an instrument panel or a door trim.

(Laminate)

A presently disclosed laminate is obtainable by stacking the presentlydisclosed vinyl chloride resin molded product with a foamed polyurethanemolded product. Examples of stacking methods that can be adoptedinclude: a method in which the vinyl chloride resin molded product andthe foamed polyurethane molded product are prepared separately and aresubsequently joined together by, for example, thermal fusion bonding,thermal adhesion, or using a commonly known adhesive; and a method inwhich raw materials of the foamed polyurethane molded product such as anisocyanate and a polyol are caused to react on the vinyl chloride resinmolded product so as to polymerize while carrying out polyurethanefoaming by a commonly known method to directly form the foamedpolyurethane molded product on the vinyl chloride resin molded product.The latter of these methods is more suitable because it involves asimple process and enables laminates of various different shapes to beobtained while ensuring reliable adhesion of the vinyl chloride resinmolded product and the foamed polyurethane molded product.

The presently disclosed laminate is highly suitable for use as anautomobile interior material such as an instrument panel or a door trim.

EXAMPLES

The present disclosure is described in more detail through the followingexamples but is not limited to these examples.

Note that in the following examples, the average degree ofpolymerization of vinyl chloride resin particles or vinyl chloride resinfine particles was calculated in accordance with JIS K6720-2 bydissolving the vinyl chloride resin particles or vinyl chloride resinfine particles in nitrobenzene and measuring the viscosity.

Furthermore, the average particle diameter (volume average particlediameter) of vinyl chloride resin particles or vinyl chloride resin fineparticles was calculated by dispersing the vinyl chloride resinparticles or vinyl chloride resin fine particles in a water tank,measuring and analyzing a light diffraction/scattering intensitydistribution using a device shown below, and thereby measuring particlesdiameters and a volume-basis particle diameter distribution.

Device: Laser diffraction particle size analyzer (SALD-2300 produced byShimadzu Corporation)

Measurement method: Laser diffraction and scattering

Measurement range: 0.017 μm to 2,500 μm

Light source: Semiconductor laser (wavelength 680 nm, output 3 mW)

Examples 1-14 and Comparative Example 1

Ingredients shown in Tables 1 and 2 with the exception of theplasticizer (trimellitate plasticizer and epoxidized soybean oil) andthe dusting agent were added into a Henschel mixer and mixed. Theplasticizer was added to the mixture after increasing the temperature ofthe mixture to 80° C. and the mixture was dried up (i.e., theaforementioned mixture changed to a dry state through absorption of theplasticizers by vinyl chloride resin particles). Thereafter, once thedried-up mixture had been cooled to 70° C. or lower, vinyl chlorideresin fine particles used as the dusting agent were added to the mixtureto produce a vinyl chloride resin composition for powder molding.

The resultant vinyl chloride resin composition for powder molding wassprinkled onto a textured mold that was heated to 250° C. and afterbeing left to melt for a time adjusted to give a vinyl chloride resinmolded sheet thickness of 1 mm (specifically, from 14 seconds to 17seconds), excess vinyl chloride resin composition for powder molding wasshaken off. Next, the mold was placed in an oven set to 200° C. and wascooled with cooling water once 60 seconds had passed. Once the mold hadcooled to 40° C., a vinyl chloride resin molded sheet of 145 mm×175 mm×1mm was removed from the mold. Various properties of the resultant vinylchloride resin molded sheet were measured by the methods describedbelow. The results are shown in Tables 1 and 2.

The measurement methods of the various properties were as follows.

(1) Initial Tensile Test

The vinyl chloride resin molded sheet was punched with a No. 1 dumbbellprescribed by JIS K6251, and tensile stress and tensile elongationthereof were measured in accordance with JIS K7113 at a tension rate of200 mm/minute and a temperature of −35° C. Note that a high tensileelongation at −35° C. indicates that a vinyl chloride resin molded sheethas superior flexibility at low temperatures.

(2) Post-Heating Tensile Test

A measurement sample was prepared as follows. Two obtained vinylchloride resin molded sheets were placed in a mold having dimensions of200 mm×300 mm×10 mm with a textured surface below the molded sheets suchthat the molded sheets did not overlap one another. A mixed solution wasprepared by mixing polymethylene polyphenylene polyisocyanate (polymericMDI) with a polyol mixture in a ratio determined to give an isocyanateindex of 98. The polyol mixture was composed of 50 parts by mass of apropylene glycol PO (propylene oxide)/EO (ethylene oxide) block adduct(hydroxyl value 28, terminal EO unit content 10%, internal EO unitcontent 4%), 50 parts by mass of a glycerin PO/EO block adduct (hydroxylvalue 21, terminal EO unit content 14%), 2.5 parts by mass of water, 0.2parts by mass of an ethylene glycol solution of triethylenediamine(product name: TEDA-L33, produced by Tosoh Corporation), 1.2 parts bymass of triethanolamine, 0.5 parts by mass of triethylamine, and 0.5parts by mass of a foam stabilizer (product name: F-122, produced byShin-Etsu Chemical Co., Ltd.). Thereafter, the resultant mixed solutionwas poured onto the two vinyl chloride resin molded sheets and the moldwas covered with an aluminum plate of 348 mm×255 mm×10 mm to seal themold. After 5 minutes, a sample (laminate) was formed, in the mold, of asurface skin formed by a vinyl chloride resin molded sheet having athickness of 1 mm lined with a foamed polyurethane molded product havinga thickness of 9 mm and a density of 0.18 g/cm³. The resultant samplewas removed from the mold.

Thereafter, the resultant sample was placed in an oven and after thesample was heated for 250 hours at 130° C., the foamed polyurethanelayer was peeled from the sample. Tensile stress and tensile elongationof the sample were measured at −35° C. in the same way as in the initialtensile test described above in section (1). Note that a high tensileelongation at −35° C. indicates that a vinyl chloride resin molded sheethas superior flexibility at low temperatures.

TABLE 1 Comparative Exam- Exam- Exam- Exam- Exam- Exam- Example 1 ple 1ple 2 ple 3 ple 4 ple 5 ple 6 Composition Vinyl chloride resinparticles⁽¹⁾ 100.0 100.0 100.0 100.0 100.0 100.0 100.0 (parts byTrimellitate plasticizer⁽²⁾ 135.0 135.0 135.0 135.0 135.0 135.0 135.0mass) Epoxidized soybean oil⁽³⁾ 5.0 5.0 5.0 5.0 5.0 5.0 5.0 Perchloricacid-treated hydrotalcite⁽⁴⁾ 4.6 4.6 4.6 4.6 4.6 4.6 4.6 Zeolite⁽⁵⁾ 2.42.4 2.4 2.4 2.4 2.4 2.4 Stearoylbenzoylmethane (β-diketone)⁽⁶⁾ 0.5 0.50.5 0.5 0.5 0.5 0.5 Zinc stearate⁽⁷⁾ 0.2 0.2 0.2 0.2 0.2 0.2 0.2Hindered amine light stabilizer⁽⁸⁾ 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Phosphiteantioxidant⁽⁹⁾ 0.6 0.6 0.6 0.6 0.6 0.6 0.6 12-Hydroxystearic acid⁽¹⁰⁾0.4 0.4 0.4 0.4 0.4 0.4 0.4 Dusting agent A⁽¹¹⁾ 20.0 — — — — — — Dustingagent B⁽¹²⁾ — 20.0 — — — — — Dusting agent C⁽¹³⁾ — — 20.0 — — — —Dusting agent D⁽¹⁴⁾ — — — 20.0 — — — Dusting agent E⁽¹⁵⁾ — — — — 20.0 —— Dusting agent F⁽¹⁶⁾ — — — — — 20.0 — Dusting agent G⁽¹⁷⁾ — — — — — —20.0 Pigment⁽¹⁸⁾ 3.7 3.7 3.7 3.7 3.7 3.7 3.7 Tensile stress (initial)@−35° C. [MPa] 21.0 21.5 22.0 22.5 23.0 22.0 22.5 Tensile stress (ater250 hours heating) @−35° C. [MPa] 24.5 25.5 26.0 26.0 26.5 26.5 27.5Tensile elongation (initial) @−35° C. [%] 200 215 210 205 210 215 205Tensile elongation (after 250 hours heating) @−35° C. [%] 145 170 170170 150 180 160

TABLE 2 Exam- Exam- Exam- Exam- Exam- Exam- Exam- Exam- ple 7 ple 8 ple9 ple 10 ple 11 ple 12 ple 13 ple 14 Composition Vinyl chloride resinparticles⁽¹⁾ 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 (parts byTrimellitate plasticizer⁽²⁾ 140.0 140.0 140.0 140.0 150.0 150.0 150.0150.0 mass) Epoxidized soybean oil⁽³⁾ 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0Perchloric acid-treated hydrotalcite⁽⁴⁾ 4.6 4.6 4.6 4.6 4.6 4.6 4.6 4.6Zeolite⁽⁵⁾ 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 Stearoylbenzoylmethane(β-diketone)⁽⁶⁾ 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Zinc stearate⁽⁷⁾ 0.2 0.20.2 0.2 0.2 0.2 0.2 0.2 Hindered amine light stabilizer⁽⁸⁾ 0.2 0.2 0.20.2 0.2 0.2 0.2 0.2 Phosphite antioxidant⁽⁹⁾ 0.6 0.6 0.6 0.6 0.6 0.6 0.60.6 12-Hydroxystearic acid⁽¹⁰⁾ 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Dustingagent A⁽¹¹⁾ 5.5 6.5 11.0 13.0 5.5 6.5 11.0 13.0 Dusting agent B⁽¹²⁾ — —— — — — — — Dusting agent C⁽¹³⁾ — — — — — — — — Dusting agent D⁽¹⁴⁾ — —— — — — — — Dusting agent E⁽¹⁵⁾ — — — — — — — — Dusting agent F⁽¹⁶⁾ 16.519.5 11.0 13.0 16.5 19.5 11.0 13.0 Dusting agent G⁽¹⁷⁾ — — — — — — — —Pigment⁽¹⁸⁾ 3.7 3.7 3.7 3.7 3.7 3.7 3.7 3.7 Tensile stress (initial)@−35° C. [MPa] 21.5 22.5 21.0 22.0 21.0 21.5 20.0 19.5 Tensile stress(after 250 hours heating) @−35° C. [MPa] 25.5 26.5 25.0 25.5 25.5 25.524.5 24.5 Tensile elongation (initial) @−35° C. [%] 215 200 205 205 220225 220 215 Tensile elongation (after 250 hours heating) @−35° C. [%]175 165 170 165 190 175 175 185 ⁽¹⁾ZEST 2500Z (vinyl chloride resinparticles ((a) vinyl chloride resin particles), average degree ofpolymerization 2,500, average particle diameter 130 μm) produced by ShinDai-ichi Vinyl Corporation ⁽²⁾TRIMEX N-08 produced by Kao Corporation⁽³⁾ADK CIZER O-130S produced by ADEKA Corporation ⁽⁴⁾ALCAMIZER 5produced by Kyowa Chemical Industry Co., Ltd. ⁽⁵⁾MIZUKALIZER DS producedby Mizusawa Industrial Chemicals, Ltd. ⁽⁶⁾Karenz DK-1 produced by ShowaDenko K.K. ⁽⁷⁾SAKAI SZ2000 produced by Sakai Chemical Industry Co., Ltd.⁽⁸⁾LA-72 produced by ADEKA Corporation ⁽⁹⁾ADK STAB 522A produced byADEKA Corporation ⁽¹⁰⁾ADK STAB LS-12 produced by ADEKA Corporation⁽¹¹⁾ZEST PQLTX (vinyl chloride resin fine particles ((d) vinyl chlorideresin fine particles having average degree of polymerization of lessthan 1,000), average degree of polymerization 800, average particlediameter 2 μm) produced by Shin Dai-ichi Vinyl Corporation ⁽¹²⁾ZEST P21(vinyl chloride resin fine particles ((c) vinyl chloride resin fineparticles having average degree of polymerization of at least 1,000 andno greater than 5,000), average degree of polymerization 1,550, averageparticle diameter 2 μm) produced by Shin Dai-ichi Vinyl Corporation⁽¹³⁾ZEST PQHP (vinyl chloride resin fine particles ((c) vinyl chlorideresin fine particles having average degree of polymerization of at least1,000 and no greater than 5,000), average degree of polymerization1,550, average particle diameter 3 μm) produced by Shin Dai-ichi VinylCorporation ⁽¹⁴⁾ZEST PQHH (vinyl chloride resin fine particles ((c)vinyl chloride resin fine particles having average degree ofpolymerization of at least 1,000 and no greater than 5,000), averagedegree of polymerization 3,600, average particle diameter 2 μm) producedby Shin Dai-ichi Vinyl Corporation ⁽¹⁵⁾Ryuron paste 860 (vinyl chlorideresin fine particles ((c) vinyl chloride resin fine particles havingaverage degree of polymerization of at least 1,000 and no greater than5,000), average degree of polymerization 1,600, average particlediameter 2 μm) produced by Tosoh Corporation ⁽¹⁶⁾Ryuron paste 761 (vinylchloride resin fine particles ((c) vinyl chloride resin fine particleshaving average degree of polymerization of at least 1,000 and no greaterthan 5,000), average degree of polymerization 2,100, average particlediameter 2 μm) produced by Tosoh Corporation ⁽¹⁷⁾Ryuron paste 960 (vinylchloride resin fine particles ((c) vinyl chloride resin fine particleshaving average degree of polymerization of at least 1,000 and no greaterthan 5,000), average degree of polymerization 4,500, average particlediameter 2 μm) produced by Tosoh Corporation ⁽¹⁸⁾DA PX-1720 Black (A)produced by Dainichiseika Color and Chemicals Mfg. Co., Ltd.

Molded products (vinyl chloride resin molded sheets) obtained throughpowder slush molding of the vinyl chloride resin compositions for powdermolding in Examples 1-14 had superior tensile properties at lowtemperatures, both initially and post-heating.

Among these examples, molded products (vinyl chloride resin moldedsheets) obtained through powder slush molding of the vinyl chlorideresin compositions for powder molding in Examples 5 and 11-14 hadparticularly superior flexibility at low temperatures.

On the other hand, in the case of a molded product (vinyl chloride resinmolded sheet) obtained through powder slush molding of the vinylchloride resin composition for powder molding in Comparative Example 1,which did not include vinyl chloride resin fine particles having anaverage degree of polymerization of at least 1,000 and no greater than5,000, the molded product had low tensile elongation at low temperaturespost-heating and had poor flexibility at low temperatures.

Examples 15-17 and Comparative Example 2

Ingredients shown in Table 3 with the exception of the plasticizer(trimellitate plasticizer, pyromellitate plasticizer, and epoxidizedsoybean oil) and the dusting agent were added into a Henschel mixer andmixed. The plasticizer was added to the mixture after increasing thetemperature of the mixture to 80° C. and the mixture was dried up (i.e.,the aforementioned mixture changed to a dry state through absorption ofthe plasticizers by vinyl chloride resin particles). Thereafter, oncethe dried-up mixture had been cooled to 70° C. or lower, vinyl chlorideresin fine particles used as the dusting agent were added to the mixtureto produce a vinyl chloride resin composition for powder molding.

The resultant vinyl chloride resin composition for powder molding wassprinkled onto a textured mold that was heated to 250° C. and afterbeing left to melt for a time adjusted to give a vinyl chloride resinmolded sheet thickness of 1 mm (specifically, from 14 seconds to 17seconds), excess vinyl chloride resin composition for powder molding wasshaken off. Next, the mold was placed in an oven set to 200° C. and wascooled with cooling water once 60 seconds had passed. Once the mold hadcooled to 40° C., a vinyl chloride resin molded sheet of 145 mm×175 mm×1mm was removed from the mold. Various properties of the resultant vinylchloride resin molded sheet were measured by the methods describedbelow. The results are shown in Table 3.

(3) Initial Tensile Test

The vinyl chloride resin molded sheet was punched with a No. 1 dumbbellprescribed by JIS K6251, and tensile stress and tensile elongationthereof were measured in accordance with JIS K7113 at a tension rate of200 mm/minute and a temperature of −35° C. Note that a high tensileelongation at −35° C. indicates that a vinyl chloride resin molded sheethas superior flexibility at low temperatures.

(4) Post-Heating Tensile Test

A measurement sample was prepared as follows. Two obtained vinylchloride resin molded sheets were placed in a mold having dimensions of200 mm×300 mm×10 mm with a textured surface below the molded sheets suchthat the molded sheets did not overlap one another. A mixed solution wasprepared by mixing polymethylene polyphenylene polyisocyanate (polymericMDI) with a polyol mixture in a ratio determined to give an isocyanateindex of 98. The polyol mixture was composed of 50 parts by mass of apropylene glycol PO (propylene oxide)/EO (ethylene oxide) block adduct(hydroxyl value 28, terminal EO unit content 10%, internal EO unitcontent 4%), 50 parts by mass of a glycerin PO/EO block adduct (hydroxylvalue 21, terminal EO unit content 14%), 2.5 parts by mass of water, 0.2parts by mass of an ethylene glycol solution of triethylenediamine(product name: TEDA-L33, produced by Tosoh Corporation), 1.2 parts bymass of triethanolamine, 0.5 parts by mass of triethylamine, and 0.5parts by mass of a foam stabilizer (product name: F-122, produced byShin-Etsu Chemical Co., Ltd.). Thereafter, the resultant mixed solutionwas poured onto the two vinyl chloride resin molded sheets and the moldwas covered with an aluminum plate of 348 mm×255 mm×10 mm to seal themold. After 5 minutes, a sample (laminate) was formed, in the mold, of asurface skin formed by a vinyl chloride resin molded sheet having athickness of 1 mm lined with a foamed polyurethane molded product havinga thickness of 9 mm and a density of 0.18 g/cm³. The resultant samplewas removed from the mold.

Thereafter, the resultant sample was placed in an oven and after thesample was heated for 250 hours at 130° C., the foamed polyurethanelayer was peeled from the sample. Tensile stress and tensile elongationof the sample were measured at −35° C. in the same way as in the initialtensile test described above in section (3). Note that a high tensileelongation at −35° C. indicates that a vinyl chloride resin molded sheethas superior flexibility at low temperatures.

Another obtained sample was placed in an oven and after the sample washeated for 600 hours at 130° C., the foamed polyurethane layer waspeeled from the sample. Tensile stress and tensile elongation of thesample were measured at −35° C. in the same way as in the initialtensile test described above in section (3). Note that a high tensileelongation at −35° C. indicates that a vinyl chloride resin molded sheethas superior flexibility at low temperatures.

TABLE 3 Comparative Example 2 Example 15 Example 16 Example 17Composition Vinyl chloride resin particles⁽¹⁾ 100.0 100.0 100.0 100.0(parts by Trimellitate plasticizer⁽²⁾ 150.0 120.0 100.0 75.0 mass)Pyromellitate plasticizer⁽¹⁹⁾ — 30.0 50.0 75.0 Epoxidized soybean oil⁽³⁾5.0 5.0 5.0 5.0 Perchloric acid-treated hydrotalcite⁽⁴⁾ 4.6 4.6 4.6 4.6Zeolite⁽⁵⁾ 2.4 2.4 2.4 2.4 Stearoylbenzoylmethane (β-diketone)⁽⁶⁾ 0.50.5 0.5 0.5 Zinc stearate⁽⁷⁾ 0.2 0.2 0.2 0.2 Hindered amine lightstabilizer⁽⁸⁾ 0.2 0.2 0.2 0.2 Phosphite antioxidant⁽⁹⁾ 0.6 0.6 0.6 0.612-Hydroxystearic acid⁽¹⁰⁾ 0.4 0.4 0.4 0.4 Dusting agent A⁽¹¹⁾ 22.0 11.011.0 11.0 Dusting agent F⁽¹⁶⁾ — 11.0 11.0 11.0 Pigment⁽¹⁸⁾ 3.7 3.7 3.73.7 Tensile stress (initial) @−35° C. [MPa] 20.0 19.5 20.0 20.0 Tensilestress (after 250 hours heating) @−35° C. 24.5 23.5 24.0 23.5 [MPa]Tensile stress (after 600 hours heating) @−35° C. 30.0 28.5 28.0 28.5[MPa] Tensile elongation (initial) @−35° C. [%] 220 220 220 210 Tensileelongation (after 250 hours heating) @−35° C. 140 160 160 160 [%]Tensile elongation (after 600 hours heating) @−35° C. 70 90 90 100 [%]⁽¹⁾ZEST 2500Z (vinyl chloride resin particles ((a) vinyl chloride resinparticles), average degree of polymerization 2,500, average particlediameter 130 μm) produced by Shin Dai-ichi Vinyl Corporation ⁽²⁾TRIMEXN-08 produced by Kao Corporation ⁽³⁾ADK CIZER O-130S produced by ADEKACorporation ⁽⁴⁾ALCAMIZER 5 produced by Kyowa Chemical Industry Co., Ltd.⁽⁵⁾MIZUKALIZER DS produced by Mizusawa Industrial Chemicals, Ltd.⁽⁶⁾Karenz DK-1 produced by Showa Denko K.K. ⁽⁷⁾SAKAI SZ2000 produced bySakai Chemical Industry Co., Ltd. ⁽⁸⁾LA-72 produced by ADEKA Corporation⁽⁹⁾ADK STAB 522A produced by ADEKA Corporation ⁽¹⁰⁾ADK STAB LS-12produced by ADEKA Corporation ⁽¹¹⁾ZEST PQLTX (vinyl chloride resin fineparticles ((d) vinyl chloride resin fine particles having average degreeof polymerization of less than 1,000), average degree of polymerization800, average particle diameter 2 μm) produced by Shin Dai-ichi VinylCorporation ⁽¹⁶⁾Ryuron paste 761 (vinyl chloride resin fine particles((c) vinyl chloride resin fine particles having average degree ofpolymerization of at least 1,000 and no greater than 5,000), averagedegree of polymerization 2,100, average particle diameter 2 μm) producedby Tosoh Corporation ⁽¹⁸⁾DA PX-1720 Black (A) produced by DainichiseikaColor and Chemicals Mfg. Co., Ltd. ⁽¹⁹⁾ADK CIZER UL-80 produced by ADEKACorporation

Molded products (vinyl chloride resin molded sheets) obtained throughpowder slush molding of the vinyl chloride resin compositions for powdermolding in Examples 15-17 had superior tensile properties at lowtemperatures, both initially and post-heating.

On the other hand, in the case of a molded product (vinyl chloride resinmolded sheet) obtained through powder slush molding of the vinylchloride resin composition for powder molding in Comparative Example 2,which did not include vinyl chloride resin fine particles having anaverage degree of polymerization of at least 1,000 and no greater than5,000, and pyromellitate plasticizers, the molded product had lowtensile elongation at low temperatures post-heating and had poorflexibility at low temperatures post-heating.

INDUSTRIAL APPLICABILITY

The presently disclosed vinyl chloride resin composition for powdermolding is highly suitable as, for example, a molding material for asurface skin of an automobile interior material such as an instrumentpanel or a door trim.

1. A vinyl chloride resin composition for powder molding comprising: (a)vinyl chloride resin particles; (b) a plasticizer; and (c) vinylchloride resin fine particles having an average degree of polymerizationof at least 1,000 and no greater than 5,000.
 2. The vinyl chloride resincomposition for powder molding of claim 1, wherein (b) the plasticizeris at least one plasticizer selected from the group consisting oftrimellitate plasticizers and pyromellitate plasticizers.
 3. The vinylchloride resin composition for powder molding of claim 1, wherein avinyl chloride resin forming (a) the vinyl chloride resin particles hasan average degree of polymerization of at least 1,000 and no greaterthan 5,000.
 4. The vinyl chloride resin composition for powder moldingof claim 1, wherein (a) the vinyl chloride resin particles have anaverage particle diameter of at least 50 μm and no greater than 500 μm,and (c) the vinyl chloride resin fine particles having the averagedegree of polymerization of at least 1,000 and no greater than 5,000have an average particle diameter of at least 0.1 μm and no greater than10 μm.
 5. The vinyl chloride resin composition for powder molding ofclaim 1, wherein an amount of (c) the vinyl chloride resin fineparticles having the average degree of polymerization of at least 1,000and no greater than 5,000 relative to a total amount of (a) the vinylchloride resin particles and (c) the vinyl chloride resin fine particleshaving the average degree of polymerization of at least 1,000 and nogreater than 5,000 is at least 5 mass % and no greater than 35 mass %.6. The vinyl chloride resin composition for powder molding of claim 1,wherein an amount of (b) the plasticizer per 100 parts by mass in totalof (a) the vinyl chloride resin particles and (c) the vinyl chlorideresin fine particles having the average degree of polymerization of atleast 1,000 and no greater than 5,000 is at least 70 parts by mass andno greater than 200 parts by mass.
 7. The vinyl chloride resincomposition for powder molding of claim 1, further comprising (d) vinylchloride resin fine particles having an average degree of polymerizationof less than 1,000.
 8. The vinyl chloride resin composition for powdermolding of claim 7, wherein (a) the vinyl chloride resin particles havean average particle diameter of at least 50 μm and no greater than 500μm, (c) the vinyl chloride resin fine particles having the averagedegree of polymerization of at least 1,000 and no greater than 5,000have an average particle diameter of at least 0.1 μm and no greater than10 μm, and (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 have an averageparticle diameter of at least 0.1 μm and no greater than 10 μm.
 9. Thevinyl chloride resin composition for powder molding of claim 7, whereinan amount of (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000 relative to a total amount of (a) the vinyl chloride resinparticles, (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000, and (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 is at least 3 mass %and no greater than 20 mass %, and an amount of (d) the vinyl chlorideresin fine particles having the average degree of polymerization of lessthan 1,000 relative to the total amount of (a) the vinyl chloride resinparticles, (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000, and (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 is at least 2 mass %and no greater than 15 mass %.
 10. The vinyl chloride resin compositionfor powder molding of claim 7, wherein an amount of (b) the plasticizerper 100 parts by mass in total of (a) the vinyl chloride resinparticles, (c) the vinyl chloride resin fine particles having theaverage degree of polymerization of at least 1,000 and no greater than5,000, and (d) the vinyl chloride resin fine particles having theaverage degree of polymerization of less than 1,000 is at least 70 partsby mass and no greater than 200 parts by mass.
 11. The vinyl chlorideresin composition for powder molding of claim 1 used in powder slushmolding.
 12. A vinyl chloride resin molded product obtainable throughpowder molding of the vinyl chloride resin composition for powdermolding of claim
 1. 13. The vinyl chloride resin molded product of claim12 used as a surface skin of an automobile instrument panel.
 14. Alaminate comprising: a foamed polyurethane molded product; and the vinylchloride resin molded product of claim 12.